Kinetics of the thermal dehydration of potassium titanium oxalate, K2TiO(C2O4)2·2H2O
The thermal dehydration reaction of potassium titanium oxalate, K2TiO(C2O4)2·2H2O, has been studied by means of thermogravimetry (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC) in nitrogen atmosphere at different heating rates. K2TiO(C2O4)2·2H2O dehydrates in a single step through a practically irreversible process. The activation energy involved and its dependence on the conversion degree were estimated by evaluating the thermogravimetric data according to model-free methods, and values of activation energy were determined for the dehydration reaction. Activation energy values were also evaluated from DSC data using isoconversional methods. The complexity of the dehydration of K2TiO(C2O4)2·2H2O is illustrated by the dependence of E on the extent of conversion, α (0.05 ≤ α ≤ 0.95).
KeywordsDehydration kinetics Differential scanning calorimetry Kinetic parameters Potassium titanium oxalate Thermogravimetry
The authors express their thanks to KSCSTE for the provision of instrumental facility.
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